Optimizing dynamical resource allocations in disaggregated data centers

ABSTRACT

Embodiments for optimizing dynamic resource allocations in a disaggregated computing environment. Data access patterns of data elements associated with a set of workloads are tracked across predetermined windows of time. The set of workloads is categorized into at least one of a plurality of classes, each class characterized by a method of data access of the data elements during the tracking of the data access patterns. Resource allocations are optimized in the disaggregated computing environment for a current iteration of the set of workloads based on the method of data access by allocating specific resources within the disaggregated data center to the current iteration of the set of workloads according to the data access patterns in real-time.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application is related to the following six Applications havingU.S. application Ser. Nos. 15/982,579, 15/982,586, 15/982,589,15/982,604, 15/982,612 and 15/982,618, each filed on even date as thepresent Application.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates generally to large scale computing, andmore particularly, to optimizing a distribution of hardware resources toassociated workloads for enhanced computing efficiency.

Description of the Related Art

A popular type of large scale computing is cloud computing, in whichresources may interact and/or be accessed via a communications system,such as a computer network. Resources may be software-renderedsimulations and/or emulations of computing devices, storage devices,applications, and/or other computer-related devices and/or services runon one or more computing devices, such as a server. For example, aplurality of servers may communicate and/or share information that mayexpand and/or contract across servers depending on an amount ofprocessing power, storage space, and/or other computing resources neededto accomplish requested tasks. The word “cloud” alludes to thecloud-shaped appearance of a diagram of interconnectivity betweencomputing devices, computer networks, and/or other computer relateddevices that interact in such an arrangement.

Cloud computing may be provided as a service over the Internet, such asin the form of “Infrastructure as a Service” (IaaS), “Platform as aService” (PaaS), and/or “Software as a Service” (SaaS). IaaS maytypically provide physical or virtual computing devices and/oraccessories on a fee-for-service basis and onto which clients/users mayload and/or install, and manage, platforms, applications, and/or data.PaaS may deliver a computing platform and solution stack as a service,such as, for example, a software development platform, applicationservices, such as team collaboration, web service integration, databaseintegration, and/or developer community facilitation. SaaS may deploysoftware licensing as an application to customers for use as a serviceon demand. SaaS software vendors may host the application on their ownclouds or download such applications from clouds to cloud clients,disabling the applications after use or after an on-demand contractexpires.

The provision of such services allows a user access to as much in theway of computing resources as the user may need without purchasingand/or maintaining the infrastructure, such as hardware and/or software,that would be required to provide the services. For example, a user mayinstead obtain access via subscription, purchase, and/or otherwisesecuring access. Thus, cloud computing may be a cost effective way todeliver information technology services. However, cloud computing mayalso be hindered by issues of resource configuration and allocationaspects, and hence, there is a fundamental need to enhance and improveupon the structures and systems supporting these services.

SUMMARY OF THE INVENTION

Various embodiments optimizing dynamic resource allocations in adisaggregated computing environment, by a processor device, areprovided. In one embodiment, a method comprises (a) tracking data accesspatterns of data elements across predetermined windows of time, the dataelements associated with a set of workloads; (b) categorizing the set ofworkloads into at least one of a plurality of classes, each classcharacterized by a method of data access of the data elements during thetracking of the data access patterns; and (c) optimizing resourceallocations in the disaggregated computing environment for a currentiteration of the set of workloads based on the method of data access byallocating specific resources within the disaggregated data center tothe current iteration of the set of workloads according to the dataaccess patterns in real-time.

In addition to the foregoing exemplary embodiment, various other systemand computer program product embodiments are provided and supply relatedadvantages. The foregoing Summary has been provided to introduce aselection of concepts in a simplified form that are further describedbelow in the Detailed Description. This Summary is not intended toidentify key features or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in determining the scopeof the claimed subject matter. The claimed subject matter is not limitedto implementations that solve any or all disadvantages noted in thebackground.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the advantages of the invention will be readilyunderstood, a more particular description of the invention brieflydescribed above will be rendered by reference to specific embodimentsthat are illustrated in the appended drawings. Understanding that thesedrawings depict only typical embodiments of the invention and are nottherefore to be considered to be limiting of its scope, the inventionwill be described and explained with additional specificity and detailthrough the use of the accompanying drawings, in which:

FIG. 1 is a block diagram depicting a hardware structure of a computingsystem, in which aspects of the present invention may be realized;

FIG. 2 is a block diagram of an exemplary cloud computing environmentaccording to embodiments of the present invention;

FIG. 3 is a block diagram depicting abstraction model layers accordingto embodiments of the present invention;

FIG. 4 is a block diagram depicting a hardware structure of adisaggregated computing environment, in which aspects of the presentinvention may be realized;

FIG. 5 is an additional block diagram depicting a hardware structure ofa disaggregated computing environment, in which aspects of the presentinvention may be realized;

FIG. 6 is a flowchart diagram illustrating a method for optimizingdynamic resource allocations in a disaggregated computing environment,in accordance with various aspects of the present invention;

FIG. 7A is a block diagram depicting a spectrum of methods of dataaccess, in accordance with various aspects of the present invention;

FIG. 7B is a block diagram depicting a data heat map, in accordance withvarious aspects of the present invention;

FIG. 8 is a flowchart diagram illustrating a method for optimizingdynamic resource allocations for cache-friendly workloads in adisaggregated computing environment, in accordance with various aspectsof the present invention;

FIG. 9 is a flowchart diagram illustrating a method for optimizingdynamic resource allocations for cache-needy workloads in adisaggregated computing environment, in accordance with various aspectsof the present invention;

FIG. 10A is a flowchart diagram illustrating a method for optimizingdynamic resource allocations for memory-friendly workloads in adisaggregated computing environment, in accordance with various aspectsof the present invention;

FIG. 10B is an additional flowchart diagram illustrating a method foroptimizing dynamic resource allocations for memory-friendly workloads ina disaggregated computing environment, in accordance with variousaspects of the present invention;

FIG. 11 is a flowchart diagram illustrating a method for optimizingdynamic resource allocations for storage-friendly workloads in adisaggregated computing environment, in accordance with various aspectsof the present invention; and

FIG. 12 is a flowchart diagram illustrating a method for optimizingdynamic resource allocations through cache-friendly and priority memoryreallocation in a disaggregated computing environment, in accordancewith various aspects of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The techniques of this disclosure preferably are implemented within thecontext of a “disaggregated” computing system wherein a “disaggregatedserver”—sometimes referred to herein as a “server entity”—is dynamicallyconstructed/composed or constitutes server resources selected from (orassigned from) shared server resource pools, namely, one or more of: acompute pool, a memory pool, an accelerator pool (e.g., a GPUaccelerator, a network accelerator, etc.), and a storage pool. As thenomenclature suggests, a “compute” pool typically constitutes physicalprocessors (such as CPUs), a “memory” pool typically constitutesphysical memory devices (such as dual-inline-memory modules (DIMM)),etc. A given shared pool preferably includes just the particularresource types, but a particular resource pool may be composed of one ormore resource sub-types. The notion of a “pool” is not intended to belimiting, as the common resources may be collected, aggregated orotherwise combined in any suitable manner. Further, a “pool” may be adedicated set of resources that have the common type or sub-type, orsome ad hoc collection of such resources. Preferably, a particularserver entity comprises server resources from one or more of the serverresource pools.

Disaggregated computing systems provide flexibility and elasticity inconstructing bare-metal computing systems for use in the cloud, toprovide on-demand flexibility to cloud users, or “tenants”. Asmentioned, a disaggregated computing system is referred to as a systemwith large pools of physical hardware resources, such as CPUs,accelerators, memory devices, and storage devices, whose connectivitywith each other individual hardware resource can be dynamically switchedwithout shutting down any hardware nor running applications. Individualhardware resources from these pools can be selected to assemble computersystems on-demand. Thus, a bare-metal computer system with a flexiblecapacity of individual computing resources may be assembled in adisaggregated system, such that workloads are computed based on hardwareresource configurations that are most suitable for the respectiveworkload. In one embodiment, for example, a system may be constructedwith an extremely high capability of memory size but with a moremoderate capacity of CPU and other resources, for a memory-intensiveworkload. This functionality is enabled by the use of point-to-pointcircuit wire level switching. All disaggregated system proposalscurrently known in the art are copy-based systems in which a processstate is copied over a memory fabric to local memory at the computationhardware because of the latency in connecting directly to the pool overthe memory fabric or over a symmetric multiprocessing (SMP) system. Thismeans that switching between computing components cannot happen inmilliseconds as can the point-to-point circuit wire level switchingmechanisms used in the present invention thereby enabling a continuous,instantaneous execution of processes even while the computing componentsare switched.

One advantageous component of disaggregated computing systems is theopportunity to perform computation between various hardware resources inways previously unattainable. For example, in most pre-configuredcomputing systems, pre-fetching techniques and data locality help tokeep cache hit rates high, enabling ultra-fast performance for the enduser. However, if the processor spends a vast amount of time finding theneeded data in the cache, it may be under-utilizing bandwidth to mainmemory. Since the disaggregated architecture permits additionalprocessing components to be connected to various memory pool modules, amethod to better utilize this bandwidth to memory modules is proposed byefficiently connecting to the memory modules from other processingcomponents (during times of low usage) to perform analytic functionswhich may lead to valuable insights about the data, or its processing.Such memory access will not pass through the usual SMP fabric connectingprocessors, and hence does not disturb inter-processor communication andcoherency when really needed, increasing efficiency further.

In another example, and in the context of the present invention, thearchitecture of disaggregated computing systems may be leveraged todynamically construct a server entity of various physical resourcesaccording to the physical locality of the data and the underlyingresources needed to complete workloads utilizing this data. Considerthat typical resource allocation mechanisms would attempt, for a singlecomputer system, to allocate resources that are physically close to oneanother to reduce system latency. However, depending on a workload'sdata access patterns executed by this computer system, these allocations(even as they may be physically close together) may have little or noeffect on performance and could lead to fragmented and non-optimalresults for the larger disaggregated framework (as the actual localityof the underlying data may be different than the locality of theresources performing the workload). Accordingly, considered is amechanism for continual resource allocation optimization which leveragesobserved system behavior (e.g., data access patterns) and the unique,resource allocation capabilities of the disaggregated system todynamically re-align compute resources to data in a way not possible intraditional systems. This re-alignment of system resources will serve tostrike a better balance between the overall disaggregated frameworkutilization and the performance of each dynamic hardware system.

It should be noted that the instant disclosure, for brevity, frequentsthe language of “resources”. In an actual implementation of the presentinvention, the resources termed herein may be comprised of CPUs,graphical processing units (GPUs), memory, storage devices, networkdevices, accelerator devices, etc. which are, again, generally pooledtogether in a shared resource pool fashion. Indeed, any hardware and/orsoftware resources as commonly known in the art are to be construedinterchangeably with “resources” or “resource types” as describedherein, as one practicing the art would appreciate.

Typically, the shared resource pools are available within the physicalconfines of a particular data center, although this likewise is not alimitation. Thus, the shared resource pools themselves may be sharedacross physical data centers. Further, a particular server entity is notrequired to be composed of resources from each of the server pools.

By way of background, but not by way of limitation, the followingdescribes a representative computer environment in which the techniquesof this disclosure (described below) may be practiced.

Turning now to FIG. 1, exemplary architecture 10 of a general computingenvironment in which the disaggregated compute system of this disclosuremay be implemented and/or comprised of is depicted. The computer system10 (which may also be referred to as “cloud computing node” 10) includesCPU 12, which is connected to communication port 18 and memory device16. The communication port 18 is in communication with a communicationnetwork 20. The communication network 20 and storage network may beconfigured to be in communication with computer systems (hosts) 24 and22 and storage systems, which may include storage devices 14. Thestorage systems may include hard disk drive (HDD) devices, solid-statedevices (SSD) etc., which may be configured in a redundant array ofindependent disks (RAID). The operations as described below may beexecuted on storage device(s) 14, located in system 10 or elsewhere andmay have multiple memory devices 16 working independently and/or inconjunction with other CPU devices 12. Memory device 16 may include suchmemory as electrically erasable programmable read only memory (EEPROM)or a host of related devices. Memory device 16 and storage devices 14are connected to CPU 12 via a signal-bearing medium. In addition, CPU 12is connected through communication port 18 to a communication network20, having an attached plurality of additional computer systems 24 and22. In addition, memory device 16 and the CPU 12 may be embedded andincluded in each component of the computing system 10. Each storagesystem may also include separate and/or distinct memory devices 16 andCPU 12 that work in conjunction or as a separate memory device 16 and/orCPU 12.

It is further understood in advance that although this disclosureincludes a detailed description on cloud computing, following, thatimplementation of the teachings recited herein are not limited to acloud computing environment. Rather, embodiments of the presentinvention are capable of being implemented in conjunction with any othertype of computing environment now known or later developed.

As previously eluded to, cloud computing is a model of service deliveryfor enabling convenient, on-demand network access to a shared pool ofconfigurable computing resources (e.g. networks, network bandwidth,servers, processing, memory, storage, applications, virtual machines,and services) that can be rapidly provisioned and released with minimalmanagement effort or interaction with a provider of the service. Thiscloud model may include at least five characteristics, at least threeservice models, and at least four deployment models.

Characteristics are as follows:

On-demand self-service: a cloud consumer can unilaterally provisioncomputing capabilities, such as server time and network storage, asneeded automatically without requiring human interaction with theservice's provider.

Broad network access: capabilities are available over a network andaccessed through standard mechanisms that promote use by heterogeneousthin or thick client platforms (e.g., mobile phones, laptops, and PDAs).

Resource pooling: the provider's computing resources are pooled to servemultiple consumers using a multi-tenant model, with different physicaland virtual resources dynamically assigned and reassigned according todemand. There is a sense of location independence in that the consumergenerally has no control or knowledge over the exact location of theprovided resources but may be able to specify location at a higher levelof abstraction (e.g., country, state, or datacenter).

Rapid elasticity: capabilities can be rapidly and elasticallyprovisioned, in some cases automatically, to quickly scale out andrapidly released to quickly scale in. To the consumer, the capabilitiesavailable for provisioning often appear to be unlimited and can bepurchased in any quantity at any time.

Measured service: cloud systems automatically control and optimizeresource use by leveraging a metering capability at some level ofabstraction appropriate to the type of service (e.g., storage,processing, bandwidth, and active user accounts). Resource usage can bemonitored, controlled, and reported providing transparency for both theprovider and consumer of the utilized service.

Service Models are as follows:

Software as a Service (SaaS): the capability provided to the consumer isto use the provider's applications running on a cloud infrastructure.The applications are accessible from various client devices through athin client interface such as a web browser (e.g., web-based e-mail).The consumer does not manage or control the underlying cloudinfrastructure including network, servers, operating systems, storage,or even individual application capabilities, with the possible exceptionof limited user-specific application configuration settings.

Platform as a Service (PaaS): the capability provided to the consumer isto deploy onto the cloud infrastructure consumer-created or acquiredapplications created using programming languages and tools supported bythe provider. The consumer does not manage or control the underlyingcloud infrastructure including networks, servers, operating systems, orstorage, but has control over the deployed applications and possiblyapplication hosting environment configurations.

Infrastructure as a Service (IaaS): the capability provided to theconsumer is to provision processing, storage, networks, and otherfundamental computing resources where the consumer is able to deploy andrun arbitrary software, which can include operating systems andapplications. The consumer does not manage or control the underlyingcloud infrastructure but has control over operating systems, storage,deployed applications, and possibly limited control of select networkingcomponents (e.g., host firewalls).

Deployment Models are as follows:

Private cloud: the cloud infrastructure is operated solely for anorganization. It may be managed by the organization or a third party andmay exist on-premises or off-premises.

Community cloud: the cloud infrastructure is shared by severalorganizations and supports a specific community that has shared concerns(e.g., mission, security requirements, policy, and complianceconsiderations). It may be managed by the organizations or a third partyand may exist on-premises or off-premises.

Public cloud: the cloud infrastructure is made available to the generalpublic or a large industry group and is owned by an organization sellingcloud services.

Hybrid cloud: the cloud infrastructure is a composition of two or moreclouds (private, community, or public) that remain unique entities butare bound together by standardized or proprietary technology thatenables data and application portability (e.g., cloud bursting forload-balancing between clouds).

A cloud computing environment is service oriented with a focus onstatelessness, low coupling, modularity, and semantic interoperability.At the heart of cloud computing is an infrastructure comprising anetwork of interconnected nodes and storage systems (e.g. storagesubsystem 20).

Referring now to FIG. 2, illustrative cloud computing environment 52 isdepicted. As shown, cloud computing environment 52 comprises one or morecloud computing nodes 10 with which local computing devices used bycloud consumers, such as, for example, personal digital assistant (PDA)or cellular telephone 54A, desktop computer 54B, laptop computer 54C,and/or automobile computer system 54N may communicate. Nodes 10 maycommunicate with one another. They may be grouped (not shown) physicallyor virtually, in one or more networks, such as Private, Community,Public, or Hybrid clouds as described hereinabove, or a combinationthereof. This allows cloud computing environment 52 to offerinfrastructure, platforms and/or software as services for which a cloudconsumer does not need to maintain resources on a local computingdevice. It is understood that the types of computing devices 54A-N shownin FIG. 2 are intended to be illustrative only and that computing nodes10 and cloud computing environment 52 can communicate with any type ofcomputerized device over any type of network and/or network addressableconnection (e.g., using a web browser).

Referring now to FIG. 3, a set of functional abstraction layers providedby cloud computing environment 52 (FIG. 3) is shown. It should beunderstood in advance that the components, layers, and functions shownin FIG. 3 are intended to be illustrative only and embodiments of theinvention are not limited thereto. As depicted, the following layers andcorresponding functions are provided:

Hardware and software layer 80 includes hardware and softwarecomponents. Examples of hardware components include: mainframes 81; RISC(Reduced Instruction Set Computer) architecture based servers 82;servers 83; blade servers 84; storage devices 85; and networks andnetworking components 86. In some embodiments, software componentsinclude network application server software 87 and database software 88.

Virtualization layer 90 provides an abstraction layer from which thefollowing examples of virtual entities may be provided: virtual servers91; virtual storage 92; virtual networks 93, including virtual privatenetworks; virtual applications and operating systems 94; and virtualclients 95.

In one example, management layer 100 may provide the functions describedbelow. Resource provisioning 101 provides dynamic procurement ofcomputing resources and other resources that are utilized to performtasks within the cloud computing environment. Metering and Pricing 102provides cost tracking as resources are utilized within the cloudcomputing environment, and billing or invoicing for consumption of theseresources. In one example, these resources may comprise applicationsoftware licenses. Security provides identity verification for cloudconsumers and tasks, as well as protection for data and other resources.User portal 103 provides access to the cloud computing environment forconsumers and system administrators. Service level management 104provides cloud computing resource allocation and management such thatrequired service levels are met. Service Level Agreement (SLA) planningand fulfillment 105 provides pre-arrangement for, and procurement of,cloud computing resources for which a future requirement is anticipatedin accordance with an SLA.

Workloads layer 110 provides examples of functionality for which thecloud computing environment may be utilized. Examples of workloads andfunctions which may be provided from this layer include: mapping andnavigation 111; software development and lifecycle management 112;virtual classroom education delivery 113; data analytics processing 114;transaction processing 115; and, in the context of the illustratedembodiments of the present invention, various resource monitoring andallocation functionality 116. One of ordinary skill in the art willappreciate that the resource monitoring and allocation functionality 116may also work in conjunction with other portions of the variousabstractions layers, such as those in hardware and software 80,virtualization 90, management 100, and other workloads 110 (such as dataanalytics processing 114, for example) to accomplish the variouspurposes of the illustrated embodiments of the present invention.

Turning now to FIG. 4, a block diagram of a disaggregated computingarchitecture is illustrated, of which is included in the cloud computingenvironment 52. Within cloud computing environment 52 is thedisaggregated computing system comprising physical hardware resources200. Physical hardware resources 200 may comprise of classifications ofthe hardware resources such as a storage device pool 202, a GPU devicepool 204, a CPU device pool 206, a memory device pool 208, and a networkdevice pool 210. The physical hardware resources 200 are incommunication with a management module 250. Management module 250 maycomprise of such components as an individual resource provisioningcomponent 252 and a resource monitor 254, each described herein.

In communication with the cloud computing environment 52, the managementmodule 250, and the physical hardware resources 200, are tenants 212A,212B, and 212 n. Tenants 212A, 212B, and 212 n may communicate with thecloud computing environment 52 by way of the management module 250, andthus the physical resources 200 provided by any signal-bearing medium.

It should be noted that the elements illustrated in FIG. 2 provide onlyan example of related components that may be included in thedisaggregated computing architecture. For example, management module 250may include other components than individual resource provisioningcomponent 252 and resource monitor 254, and physical hardware resources200 may include other component classifications than storage device pool202, GPU device pool 204, CPU device pool 206, and memory device pool208, and network pool 210, while staying in the spirit and scope of thepresent invention. Additionally, the duties of the management module250, and thus the components therein, may be performed and comprised ofphysical components, computer code, or a combination of such.

In one embodiment, the management module 250 interacts with individualtenants 212A-n to receive workload requests and locate the best suitablehardware resources for the given workload. Individual hardware resourcesof the physical hardware resources 200 are tracked and a mapping ismaintained between each respective tenant 212A-n and respective assignedhardware resource. Each hardware resource is identified using a uniqueidentifier. This identifier may be a physical identifier (e.g., barcode)and/or a virtual identifier (e.g., code based). The management module250, or any other suitable modules or means known in the art may be usedto accomplish these mechanisms.

FIG. 5 is a block diagram illustrating the physical hardware resources200 portion of FIG. 4. Included in the storage device pool 202 arestorage devices 202A, 202B, and 202 n. The GPU device pool 204 includesGPU devices 204A, 204B, and 204 n. The CPU device pool 206 includes CPUdevices 206A, 206B, and 206 n. The memory device pool 208 includesmemory devices 208A, 208B, and 208 n. Finally, the network device pool210 includes network devices 210A, 210B, and 210 n. Each aforementionedhardware resource may be in communication with an additional one or moreaforementioned hardware resources via a signal-bearing medium.

Within physical hardware resources 200, each hardware resource appearingin solid line (i.e., storage device 202A, GPU device 204A, CPU device206A, memory device 208A, and network device 210A) are assigned hardwareresources to one or more tenants (i.e., tenants 212A, 212B, 212 n).Hardware resources appearing in dashed line (i.e., storage devices 202B,202 n, GPU devices 204B, 204 n, CPU devices 206B, 206 n, memory devices208B, 208 n, and network devices 210B, 210 n) are unassigned hardwareresources which are available on-demand for a respective tenant 212A-nworkload.

Each respective tenant 212A-n may be assigned individual respectivehardware resources 200 in arbitrary quantities. In one embodiment, eachrespective tenant 212A-n may be assigned an arbitrary quantity of anindividual respective hardware resource 200 within a limit of totalsystem capacity and/or an available quantity of the respective hardwareresources 200. For example, a memory device 208A-n allocated from thememory pool to a respective tenant 212A-n may be provided in a minimalunit of allocation (e.g., a byte or word) up to a limit of total systemcapacity and/or an available quantity of the memory devices 208A-n.

In another embodiment, each respective tenant 212A-n may be assignedindividual respective hardware resources 200 within a quantum stepsizing restriction. For example, memory devices 208A-n may need to beallocated on quantum sizes of full or half of memory DIMM units, toassure full bandwidth from the respective memory device 208A-n to theprocessor when reading/writing data. This is especially true in adisaggregated system since the memory device 208A-n is directlyconnected via fiber/optical switch to the processor memory unit (forread/write memory transactions) as if it was locally connected to theprocessor chip, but rather may be a small distance (e.g., 1 meter) awayin location. In another example, because the disaggregated system is notbased on virtual components but rather physical components (i.e., actualchips than cores or VMs), the quantum sizing restriction may requirethat a minimum of one CPU device 206A-n be assigned to a tenant 212A-n,with additional CPU devices 206A-n being provisioned to the tenant212A-n in two, four, etc. quantities.

Optimizing Dynamic Resource Allocations

In various embodiments, the functionality of the present inventionleverages the point-to-point circuit wire level switching and hardwarepooling attributes of disaggregated systems to provide an efficientmechanism for rolling software upgrades. As aforementioned, in this typeof disaggregated system, like resources are organized into pools whichcan be directly connected to resources of another pool. An effectivelyprovisioned “system” will be composed of a set of computing resourcesconnected in a point-to-point fashion to memory and storage resources,etc.

Thus, in a disaggregated system, resources may be allocated to thecomposed system based on various observed data access patterns ofworkloads which would otherwise be unattainable using fixed-hardwaremechanisms. This allows resources to be allocated, in substantiallyreal-time, to specific workloads (or workload types) which may benefitfrom running on a specific resource or set of resources being in aspecific physical locality in relation to one another. Further, thisfunctionality aids in achieving an optimal balance between utilizationof the disaggregated framework (which optimally is a high utilizationsuch that resources are not left stagnant) and the performance of eachdynamically constructed system in the disaggregated environment.

First, considered is a method of data access analysis which functions asa data heat map. The heat map tracks access patterns across windows oftime on a data element basis, which data elements are associated withworkloads performed by the disaggregated system. The disclosedfunctionality additionally provides techniques to reduce the overhead(if any) caused by creating and maintaining the data heat map. Thishelps to position the storage/memory hierarchy of the disaggregatedframework as simply a range of mediums with different properties (e.g.,speed and physical locality in relation to the processor) which could beexploited (i.e., combined with the inherent dynamicallocation/reallocation functionality of the disaggregated system) todrive the balance between the overall disaggregated frameworkutilization and the performance of each dynamically constructed hardwaresystem.

Once the data analysis methodology is in place using the mechanisms ofthe data heat map, workloads and/or disaggregated systems are then ableto be classified into a number of classes, each optimized according totheir method of data access and provided allowances unique to theiraccess pattern. Below are described a few exemplary data access patternclasses.

Cache-Friendly—In this system, most data access can be met by the cache.In other words, workloads/systems exhibiting cache-friendly behavior areable to access most of their underlying data (i.e., beyond a certainthreshold) in the cache of the processor(s). Cache-friendly workloadscan afford to be executed on systems in which memory and storageresources are further away (physically, in relation to the processor(s)executing the workload) because these workloads will seldom experiencestorage and memory latency. In addition, the continuing trend oftechnology miniaturization provides a large range of CPU operatingmodels and clock speeds which can be used to hide any performance impactof moving memory further away in systems with cache-friendly workloads.

Cache-Needy—This system's data access pattern exhibits behavior whichsuggests that it is not yet cache-friendly, but there is enough commondata use that the system could be cache-friendly if the workload/systemwere provided additional (i.e., a larger) cache.

Memory-Friendly—In this system, the data access pattern exhibitsbehavior which does not suggest that the workload/system could be mostlysatisfied through a large cache, however it is determined that most dataaccess of this workload/system can be met by memory. These workloads canbe advantaged by moving their underlying data to closer or faster memorymediums.

Storage-Friendly—Data access patterns from these systems exhibitbehavior which suggests that these workloads/systems would not be mostlysatisfied through a larger cache or by otherwise altering memoryalignment in relation to the locality of the underlying data; however,these systems exhibit storage access patterns which when learned, can beused to pre-fetch forecasted data elements in the appropriate storagecache medium.

Once the data access analysis is performed, the optimization process(which will be discussed in detail, following) may be performed at anytime (e.g., such as at predetermined intervals or triggered from systemevents). In some exemplary embodiments, however, the optimization may betriggered according to: (a) A predetermined interval given by theoverall system administrator. This interval should be chosen in a mannerwhich reflects how sensitive the system should be to the overhead of theperformance optimization process; and/or (b) Special system triggerssuch as the initial allocation of a new dynamically constructed hardwaresystem, hardware component failure, and/or any system alert ofperformance degradation or SLA violation (meaning the performance of theworkload being performed is not adhering to its defined SLA).

Generalizing these concepts, FIG. 6 illustrates a method 600 foroptimizing dynamic resource allocations in a disaggregated computingenvironment. The method 600 (and all subsequent methods disclosedherein) may be performed in accordance with the present invention in anyof the environments depicted in FIGS. 1-5, among others, in variousembodiments. Of course, more or fewer operations than those specificallydescribed in FIG. 6 may be included in the methods, as would beunderstood by one of skill in the art upon reading the presentdescriptions.

Each of the steps of the method 600 (and all subsequent methodsdisclosed herein) may be performed by any suitable component of theoperating environment. For example, in various embodiments, the method600 may be partially or entirely performed by a processor, or some otherdevice having one or more processors therein. The processor, e.g.,processing circuit(s), chip(s), and/or module(s) implemented in hardwareand/or software, and preferably having at least one hardware componentmay be utilized in any device to perform one or more steps of the method600. Illustrative processors include, but are not limited to, a CPU, anApplication Specific Integrated Circuit (ASIC), a Field ProgrammableGate Array (FPGA), etc., combinations thereof, or any other suitablecomputing device known in the art.

The method 600 begins by tracking data access patterns of data elementsacross predetermined windows of time, where each of the data elementsare associated with a set of workloads (step 602). At step 604, the setof workloads are categorized into at least one of a plurality ofclasses, each class characterized by a method of data access of the dataelements during the tracking of the data access patterns. The method ofdata access may be considered to include whether the workloads primarilyaccess (or otherwise are predicted to access) their data elements incache, in memory, or in secondary storage resources. At step 606,resource allocations in the disaggregated computing environment for acurrent iteration of the set of workloads are optimized based on themethod of data access by allocating specific resources within thedisaggregated data center to the current iteration of the set ofworkloads according to the data access patterns. This allocation of thespecific resources to the dynamically constructed disaggregated serveris performed in real-time or substantially in real-time.

Accessing Data Access Patterns to Determine System/WorkloadClassification

In various embodiments disclosed herein, the data access patterns of theworkloads executing in the disaggregated framework are monitored andmodeled in order to determine where each workload lies in the spectrumof data access. FIG. 7A is a block diagram depicting a graph 700 of thisspectrum of methods of data access. Graph 700 illustrates the relationbetween the frequency of data access to memory and storage resources andthe cache-friendly, cache-needy, memory-friendly, and storage-friendlybehaviors utilized to identify the data access patterns. Namely, as thefrequency of tracked data access increases to (slower) larger memory andstorage resources, the workloads associated with this data accessexhibit the cache-friendly, cache-needy, memory-friendly, andstorage-friendly behaviors, and are classified therein respectively.

This classification defines what techniques may be used to enableoptimal cache, memory, and storage allocation to the disaggregatedsystem. In some embodiments, a data heat map may be advantageously usedto develop the data access tracking model, however, the data accessmodeling may take many forms also including data request monitoring,memory/storage link monitoring, etc. as one skilled in the art wouldappreciate.

In some implementations, the data heat map may comprise a table of arespective workload's data scope and its most recent access pattern.Therefore, to build the data heat map 750 as depicted in FIG. 7B, as theworkload accesses new data, an additional row is added to the tablewherein the number of times this workload's data is accessed is tracked(i.e., as an integer value of a frequency of access). In this case,accessing new data is referring to a data element (like a variable), notthe data's value (as the value for that data could change which wouldsimply count as an additional access to that data). The location of thedata is also updated in the data heat map 750 as it is accessed (e.g.,within which tier of memory or storage, etc.); such that if a dataelement is accessed in memory and then subsequently moved to cache,there will not be two rows provided for the same data. Rather, one rowwould be provided with the latest access location information.

The data heat map 750 may use a sampling methodology (i.e., a samplingalgorithm) to reduce overhead of comprehensive monitoring of each dataelement of the workload, such that the data heat map 750 is updated atcertain intervals. Because patterns of frequent use are ultimatelysought after for the data elements, these patterns should still show upwith a given sampling of the overall data. Moreover, course data groupsof the data elements may be used for each row of data access (such thatseveral data elements are grouped into a course group). This may be aconfigurable parameter by a system administrator, etc. which will helpoperators balance the overhead with the effectiveness of the process ofbuilding the data heat map 750. Upon building and maintaining the dataheat map 750, the classes of data access may then be determined for dataelements or groups of data elements associated with respective workloadsas follows.

Monitoring Cache-Friendliness: As mentioned, cache-friendly behavior isseen when a sufficient quantity and percentage of the data requestsassociated with a workload are fulfilled by the data in the processorcaches (e.g., a quantity and/or percentage above a certain threshold). Acache-friendly classification may be determined by analyzing the dataheat map 750 for a configurable number of intervals for sufficient count(above a predefined threshold) of data requests fulfilled by aparticular cache identifier and a sufficient percentage (above apredefined threshold) of those data requests compared to the total datarequests for the disaggregated system.

It should be noted that alternate means of approximating cache-friendlybehavior may include using recent memory counters, memory linkutilization, etc. to monitor the workload's access pattern to determinethe quantity and relative percentage of data requests satisfied throughthe processor cache.

Monitoring Cache-Neediness: Cache-needy behavior is seen when thedisaggregated system or workload's percentage of data requests fulfilledby the cache is too low to be considered cache-friendly, however thedata access pattern of the workload shows frequent and reoccurringaccess to a limited set of data blocks outside of the processor cache.In this scenario, having access to a larger cache would enable thissystem or workload to become cache-friendly.

The detection of such cache-needy workloads may be detected in manyways, including examining the data heat map 750 for conditions where themajority of data requests can be fulfilled by an (feasibly) increasedcache size. Allocating additional CPU resources to a target system (atarget, dynamically constructed disaggregated server) will increase thetarget system's cache. Therefore, workloads exhibiting cache-needybehavior should be considered as workloads which could becomecache-friendly if a small number of allocated CPU cache-sizes would aidein fulfillment of the workload's data request through the processorcaches.

Monitoring Memory-Friendliness: Memory-friendly behavior is seen whendata requests associated with the workload can be fulfilled mostly(e.g., beyond a certain threshold) within memory, however the memorywill be accessed often. Workloads exhibiting this memory-friendlybehavior may benefit from memory devices holding the workload data to beaccessed being (physically) closer to the compute components.

Memory-friendly behavior of workloads may also be detected in many ways,including examining the data heat map 750 for conditions where a highnumber and high percentage (e.g., above a predefined threshold) of datarequests of the workload were satisfied through memory access.

Monitoring Storage-Friendliness: Storage-friendly behavior is seen whendata requests associated with the workload must be frequently fulfilledfrom storage devices, however the data requests are determined to befulfilled in a manner which can be modeled. In this instance, sectionsof data in the storage devices may be identified which would benefitfulfillment of the workload's data requests if this data is temporarilymoved to a faster medium in the memory/storage hierarchy.

Again, storage-friendly behavior of workloads may also be detected inmany ways, including examining the data heat map 750 for conditionswhere a high number and high percentage of data requests (e.g., beyond acertain percentage threshold) have had to be satisfied through storageaccess. In addition to determining that the workload exhibits thestorage-friendly behavior, the workload must meet one of the followingpredictability conditions: (a) Modeling accuracy—the workload mustexhibit a storage access pattern which can be modeled and predicted witha high-level of accuracy. This ensures that the data selected has a highchance of being used in the faster storage medium; and/or (b) Smalldataset—the workload's dataset must be small enough (as determined by athreshold, for example) that the whole dataset for the entire workloadis able to be moved to the faster storage medium. In this case ofdetermining the workload is associated with a small dataset, there is noneed to predict the sections of data which would likely be used.

As eluded to previously, workloads themselves may be monitored todetermine which class of access pattern they best fit into, however, thedynamically constructed disaggregated systems may also be allocated withresources built to serve a specific class previous to or subsequent toaccepting such classes of workloads. In other words, “workloads” and“disaggregated systems” may be used somewhat interchangeably, as boththe workloads requesting data and a given disaggregated system may eachexhibit behavior pertaining to a certain class of data access. Ofcourse, both the workloads and thereby the disaggregated systemsperforming the workloads may be allocated (or de-allocated) additionalor fewer physical resources in substantially real time to account forthe class of data access the workload/system ultimately fits into.

It should be noted that when a new disaggregated system allocationrequest is made (e.g., for performing a given workload), theworkload/system is assumed to be cache-friendly unless configuredotherwise by the system administrator/user. This is becausecache-friendly systems tend to be the most relaxed (or flexible) of theclassifications from a resource allocation point of view, as memory andstorage resources may be allocated which are further away and in slowermediums than the processing component. This assumption permitsflexibility in the overall framework to select convenient (physical)locations to allocate the system's memory and storage resourcestherefrom. If the assumption is correct, the disaggregated system willseldom experience any penalty of a larger distance to memory and storageresources located away from the processing component. If the assumptionis incorrect and this causes SLA challenges of workloads being performedby the system, the new resource allocations will be quickly addressed inthe overall optimization process or a system-specific optimizationprocess (such as triggered by SLA violations, etc.).

Optimizing a Target System based on the Monitored System/WorkloadClassification

In describing the optimization for each class of data access, thefollowing global parameters are used and defined as:

-   -   Hop=A metric used to determine distance between components        (e.g., the physical distance separating a processing component        and a memory or storage component). This metric may comprise a        number of time segments (e.g., 1 hop=1 nanosecond, etc.) or the        metric may comprise a physical hop (i.e., a number of link        segments between components);    -   Hop_window=A metric which determines how many “hops” should be        considered as equivalent during each iteration of the        optimization process;    -   CF_Threshold[x]=Predefined cache-friendliness thresholds which        determine the aggressiveness of the cache-friendly re-allocation        procedure for each hop x. These thresholds are defined by a        system administrator;    -   CF_MemUnit[x][i]=A table containing the access pattern of memory        unit i at hop x. This is a metric which will be compared to the        CF_Threshold of hop x during the cache-friendly re-allocation        procedure;    -   Clockspeed_maximum=A maximum percentage of normal clock speed        able to be safely set for a given processing component (e.g.,        1.10=10% overclocking); and    -   Clockspeed_step=A unit amount of increased clock speed allowed        during one optimization iteration to achieve better performance.

In some embodiments, to determine the disaggregated system target forlocal optimization, at least two optimization techniques may beperformed. The first is what will be referred to as “generaloptimization”. When the optimization process is run in a generaloptimization capacity (e.g., triggered at a predetermined interval inputby the system administrator or triggered by a hardware failure, forexample), a first disaggregated system attempts to identify alldisaggregated systems within the framework in need of resources forperforming various workloads, and optimizes the resource allocations tothese systems. The optimization process may, again, be performed in aloop fashion at determined intervals, and a target disaggregated systemwill need to be determined for each pass of the optimization loop. Thefirst targeted disaggregated system for optimizing may be determined byexamining each disaggregated system in the highest service class (e.g.,according to an SLA between the disaggregated system and a given tenant)to identify the system which is missing its SLA or otherwise isperforming the most poorly. Once selected, the optimization process isexecuted for that target system, and once all systems in the highestservice class are examined and optimized, the disaggregated systemsbelonging to the next highest service class are examined and optimized,and so on. This may be summarized as the current target=thedisaggregated system having the poorest performance in its given serviceclass.

The second optimization technique is referred to as a triggeredoptimization. In many situations, an event which triggers theoptimization process will already be specific to a particulardisaggregated system (the target system). In this case, the optimizationis performed only for this target system and only one pass (oneiteration) through the optimization process is needed to optimize onlythis system. For example, in an initial allocation example where a newdisaggregated system is dynamically constructed and/or a disaggregatedsystem has its resource allocations substantially changed, it is the newsystem having the new allocations thereto which is considered as thetarget for optimization. If a workload/system SLA violation is thetrigger, the target system is the system whose SLA is violated. This maybe summarized as the current target=the disaggregated system whichtriggered the optimization.

The following detailed cases are described in the context of thetriggered optimization technique (such as a workload/system SLAviolation). However, it should be appreciated that the optimizationprocess may be performed as described above in the same manner (havingthe same steps described subsequently) using the general optimizationtechnique as triggered by an administrator, as the disaggregated systemhaving the poorest performance, or many other related triggeringmethods.

Cache-Friendly Workload Optimization

FIG. 8 is a flowchart diagram illustrating a method 800 for optimizingdynamic resource allocations for cache-friendly workloads in thedisaggregated computing environment. In the case the targetdisaggregated system is cache-friendly (as observed from the workload'sdata access pattern) and this system/workload is determined to bemissing (failing to meet) its SLA for a given workload (at step 802),optimization includes performing memory movement and increasing clockspeed of the target system's processor(s) by a given step, as will bedescribed. Otherwise, if the workload is not missing its SLA or thesystem is otherwise performing satisfactorily at step 802, the method800 ends at step 808.

Returning to step 802, if the cache-friendly target system/workload isdetermined to fail to meet its SLA (or otherwise performing poorly),memory for these workloads can be de-allocated (moved) away to a furtherdistance without hurting performance, allowing other workloads toallocate the closer memory to the system they are executing upon (step804). Because the optimized workload exhibits cache-friendly behavior,increasing processor clock speed (at step 806) will increase thepercentage of the time cache hits operate even faster. Further,overclocking the processer may help increase performance or mitigate anyadverse effects of moving the memory further away.

This technique should also be used as part of the general optimizationtechnique when cache-friendly workloads are missing predetermined goals,as well as a technique to reduce the already low impact of moving memoryunits of cache-friendly workloads to free up space for cache-unfriendlyworkloads. This process may be summarized as: if(target[Clockspeed]<Clockspeed_maximum) thentarget[Clockspeed]=target[Clockspeed]+Clockspeed_step.

Cache-Needy Workload Optimization

FIG. 9 is a flowchart diagram illustrating a method 900 for optimizingdynamic resource allocations for cache-needy workloads in thedisaggregated computing environment. In the case the targetdisaggregated system is cache-needy (as observed from the workload'sdata access pattern) and this system/workload is determined to bemissing (failing to meet) its SLA for a given workload (at step 902),optimization includes allocating more processing cores to increase totalamount of cache available to the target system, as will be described.Otherwise, if the workload is not missing its SLA or the system isotherwise performing satisfactorily at step 902, the method 900 ends atstep 906.

Returning to step 902, if the cache-needy target system/workload isdetermined to fail to meet its SLA (or otherwise performing poorly), inorder to increase the number of processing cores to the system, freecores must be identified or busy cores must be made available from lowerimportance systems or systems which exhibit cache un-friendly behavioron the same processor, and these cores are donated to the target systemto increase cache volume thereof, as will be described (step 904). Thefollowing description illustrates the moving of a single processor coreto the target system (to gradually impact performance), however animplementation may also include moving multiple cores to reach specificperformance goals.

First, if there are available cores on this (same) processor of thetarget system which could be allocated to this processor to increase theamount of total cache available, an available core is allocated to thistarget system, and the process ends.

If there are not any available cores on this processor, variousdisaggregated systems utilizing the same processor are cycled through toidentify a lower-class donor core (a system having allocated cores onthe same processor as the target system), starting with the lowestpriority workloads and ending with the workloads which are just oneservice class lower than the target system's service class. If a donorcore is located, the following steps are followed: (a) The donor's coreis moved to another processor. This is performed by (i) finding a freecore such that if there are free cores in other processors, one of thesecores is allocated to the donor system; (ii) copying cache data from theold core to the new core instantly allocated to the donor; and (iii)freeing the old core which the donor is donating to the target system.(b) The freed core is then allocated to the target workload of thetarget system.

If there are not any available cores or lower-service classdisaggregated systems utilizing this processor, various disaggregatedsystems utilizing the same processor are cycled through to identify aprocessor in a system at the same service level as the target system topick a cache-unfriendly donor which can afford to donate cache to thetarget system. In this instance, the following steps are performed:

(1) A donor core is identified in a system at the same service level,considering that (a) those donor cores are excluded who could violatetheir own SLA when donating. For example, the donor core cannot bewithin a predetermined percentage of violating its SLA (where thepredetermined percentage may be set by the system administrator todetermine the aggressiveness of the algorithm); (b) those donor coreswho would violate reserved allocations if cores were donated areexcluded; and (c) those donor cores chosen are ensured to be“cache-unfriendly enough”. For example, even cache-unfriendly systemsmay suffer performance penalties when losing cache, and therefore onlysystems with components having cache-friendliness metrics which exceed athreshold designed for cache donation are considered. This threshold mayalso be set by the system administrator to determine the aggressivenessof the algorithm. This algorithm may be summarized as:Cache-Unfriendliness=% of data requests not met by the cache.

(2) If a donor is identified, another core is attempted to be identifiedto allocate (replace) the donor core of the donor system (of course,another core may not be able to be found to replace the donor core,however the donor core would not be considered if it were at risk ofviolating its system's SLA). If the donor core is allocated to thetarget system and another core is identified to replace the donor coreof the donating system: (a) the donor's core is moved (allocated) toanother processor by (i) finding a free core, wherein if free cores areidentified in other processors, one of them is allocated to the donorsystem; and (ii) the cache data is copied from the free core to thereplacement core just allocated to the donor system. (b) Subsequent toallocating the free core to the donor processor and copying the cachedata thereof, the donor core (which the donor is donating to the targetsystem) is freed and allocated to the target system/workload.

Memory-Friendly Workload Optimization

FIG. 10A is a flowchart diagram illustrating a method 1000 foroptimizing dynamic resource allocations for memory-friendly workloads inthe disaggregated computing environment. In the case the targetdisaggregated system is memory-friendly (as observed from the workload'sdata access pattern) and this system/workload is determined to bemissing (failing to meet) its SLA for a given workload (at step 1002),optimization includes attempting to find and allocate closer hop memoryto the target system, as will be described. Otherwise, if the workloadis not missing its SLA or the system is otherwise performingsatisfactorily at step 1002, the method 1000 ends at step 1008.

Returning to step 1002, if the memory-friendly target system/workload isdetermined to fail to meet its SLA (or otherwise performing poorly), theamount of the target system's memory that is furthest away isdetermined, closer hop memory to the target system's processingcomponent is then identified (step 1004), and the memory determined tobe furthest away from the target system is then targeted forreallocation to the hop memory closer to the processing component (step1006). The following description illustrates this memory reallocation inaccordance with the method 1050 for optimizing memory placement in FIG.10B.

The method 1050 begins (step 1052) by determining the amount of thetarget system's memory that is furthest away, and iterating through eachhop to determine the closest memory unit(s) to reallocate this system'smemory thereto (step 1054). If the target system is an initial request(i.e., the system did not exist prior), RemMemRequest is used as therepresentation of the actual amount of memory requested. Conversely, ifthe target system is an existing system, RemMemRequest is represented asthe amount of memory further than 1 Hop_window away. Additionally,assume that hop x starts at 1 (1 Hop_window).

It should be noted that if memory is already allocated to this targetsystem from the current hop, there is no need to attempt to reallocatethe RemMemRequest (such that RemMemRequest−=Allocated {target}[hop])(step 1056). Next, using these described variables, a determination ismade (step 1058) as to whether the memory request can be totallyfulfilled with free memory within hop x (RemMemRequest<=FreeMem[hop]).If the requested amount of memory is available at the determined hop,these memory units (referenced as RemMemRequest) are allocated to thetarget system (step 1060) and the method 1050 ends successfully (step1062).

Returning to step 1058, if the memory request cannot be totallyfulfilled with free memory at hop x (RemMemRequest>FreeMem[x]), acache-friendly and priority reallocation procedure is performed(referred to as the “special method” described infra) at hop x to freeup hop x memory (step 1064). Subsequent to performing the cache-friendlyand priority reallocation procedure, a determination is made (step 1066)as to whether the memory request can then be totally fulfilled with freememory at hop x (RemMemRequest<=FreeMem[hop]). If the memory request canthen be fulfilled at step 1066, the memory units are reallocated to thetarget system at step 1068, and the method 1050 again ends successfully(step 1062).

Returning to step 1066, if even subsequent to the cache-friendlyreallocation procedure, the memory request still cannot be totallyfulfilled with free memory at hop x (RemMemRequest>FreeMem[x]), theavailable free memory allocated at hop x (FreeMem[x]) is reallocated tothe workload (step 1070), and RemMemRequest is updated to show theactual amount of memory resources requested pursuant to thisreallocation (RemMemRequest=RemMemRequest−FreeMem[x]). A determinationis then made (step 1072) as to whether this hop is the last hop (the hopclosest to the target system or hop=MAX). If no additional hops exist toexamine, the method 1050 ends as a failed attempt (step 1076).Otherwise, if additional hops exist to be examined at step 1072, the hopcounter is advanced to x+1 (step 1074), and the method 1050 returns tostep 1056, where if there is already memory allocated to the targetsystem at this new hop, there inherently is no need to reallocate thismemory to the target system as(RemMemRequest=RemMemRequest−Allocated[target][x]). The reallocationprocess is then restarted anew where available free memory at hop x isreallocated to the workload, and RemMemRequest is updated to distinguishthe available resources requested/utilized.

Storage-Friendly Workload Optimization

FIG. 11 is a flowchart diagram illustrating a method 1100 for optimizingdynamic resource allocations for storage-friendly workloads in thedisaggregated computing environment. In the case the targetdisaggregated system is storage-friendly (as observed from theworkload's data access pattern) and this system/workload is determinedto be missing (failing to meet) its SLA for a given workload (at step1102), optimization includes temporarily allocating a faster portion ofthe storage/memory spectrum (this could be seen as a dynamic storagecache) to the blocks of data which are forecasted to be accessed for thenext x number of time intervals (as predicted by analysis of the dataheat map 750), as will be described. Otherwise, if the workload is notmissing its SLA or the system is otherwise performing satisfactorily atstep 1102, the method 1100 ends at step 1108.

Returning to step 1102, if the storage-friendly target system/workloadis determined to fail to meet its SLA (or otherwise performing poorly),data or portions of a dataset (associated with the workload) which willbe accessed is predicted or forecasted (step 1104), and this data isproactively moved to a faster storage medium for performanceimprovements when the data is subsequently accessed (step 1106). Asmentioned, these blocks of data are forecasted to be accessed for thenext x number of time intervals, where the number of intervals whichwill be taken into account “x” can be dependent on the confidence of themodel and the aggressiveness setting of the system.

In the disaggregated framework, there are several pools of various typesof storage devices (e.g., PCM, Flash, HDD, etc.) which may becategorized by their speed—store[1 . . . n] where store[1] is thefastest (e.g., PCM storage) and store[n] is the slowest (e.g., tapestorage). Therefore, in the case of observed storage-friendly workloads,one of the faster storage mediums is attempted to be leveraged as cachefor the target system to lessen the impact of the system's frequentstorage access by performing the following steps. First, the mostfrequently accessed data groups (cache_set) are determined andforecasted for the target system's next “x” intervals. Next, consideringthat RemStoreRequest=size(cache_set), for each data element/data groupin the forecasted cache_set (starting with the cache_set data elementswhich are the furthest away from the target system), a determination ismade as to whether a faster storage medium exists which could be used asa cache for the target system as follows:

(1) When the determination is made that a faster storage medium exists,another determination is made as to whether there exists free storagespace in this storage medium, and if free space exists, this isrepresented as (FreeStore[storeID]) in astoreID<current_data_element.storeID, where storeID references thestorage identification (ID) of the faster medium; and (2) If it isdetermined that there exists no free storage space, in astoreID<current_data_element.storeID, other storage caches from lessimportant (lower priority) workloads may be written back to this storageand removed to free space for this workload's (the higherpriority/target system's) storage cache.

Once the determination is made that a faster storage medium exists andfree storage space exists in this medium, any faster storage identifiedabove can be allocated as additional storage to the target system,however the target system will use it as a write-back cache for thecurrent data element (current_data_element). It should be noted thatpoint-to-point connections (inherent in the disaggregated framework) canbe made between the storage at storeID (the cache destination) andcurrent_data_element.storeID (the current location) to enable quickcopying of the data therein. Further, at the end of “x” intervals, thedirty data may be written back to the current_data_element through apoint-to-point connection and the storage cache may be removed.Additionally and/or alternatively, the storage cache may be refreshed byleveraging the forecast for the next “x” time intervals by use of thedata heat map 750.

Special Method: Cache-Friendly and Priority Reallocation

As mentioned previously, to free up memory at a particular hop (hop x),a priority reallocation procedure may be performed so as to free memoryfor allocation during the memory-friendly optimization procedure asdescribed. As illustrated by the method 1250 in FIG. 12, this specialreallocation procedure begins (step 1252) by reading the configurationparameter CF_Threshold[x] to determine the aggressiveness of thisparticular cache-friendly reallocation procedure at hop x, andexamining, for each dynamic hardware system memory unit (i) in hop x,the service class (serviceclass(i)) related to this candidate memory(step 1254). Those memory units in the lowest service class are firstexamined.

Next, a determination is made (step 1256) as to whether the serviceclass of the identified candidate memory units is less than (a lowerpriority than) the service class of the target system. If the candidatememory is determined to be assigned to a lower priority class (if(serviceclass(i)<serviceclass(target)), the candidate memory units aremoved to a hop further away (in physical distance) by identifying freememory unit(s) j in a subsequent hop z (z is greater than x) are lessimportant (have a lower priority) than workload memory unit j in hop z.Data is then copied from memory unit i in hop x to newly freed memoryunits j in hop z, and the candidate's effective system is updated toshow the new amount of memory assigned to the system by updating theprocessor link to memory to point to the new memory unit j in hop z.Finally, the memory unit i in hop x is freed to make it available forthe target workloads of the target system (represented asmemory_needed=memory_needed−memoryunit(i)) (step 1258).

Subsequent to moving the candidate memory and freeing the memory unitsto be allocated to the target system, a memory unit counter i isincremented (i=i+1), and a determination is made (step 1260) as towhether the amount of memory needed by the target system has been freedby the first iteration of the method 1250. If the memory requestrequirement has been satisfied, the method 1250 ends successfully (step1262). Otherwise, a next candidate memory unit in the same service classis examined, or, if no additional memory units exist in this serviceclass, memory units allocated to a next highest service class are thenexamined (step 1264). This process is repeated until memory_needed<=0 orall memory units i in hop x have been exhausted (by returning to step1256).

Returning to step 1256, if the candidate memory unit's service class ishigher than the target system's service class, the method 1250 advancesto again iterating through each candidate memory unit at the given hopwithin the target system's service class (step 1266). Next, if thecandidate memory unit exhibits cache-friendly behavior(CF_Metric[candidate]<=CF_Threshold), the candidate memory unit's datais moved to a hop further away (in distance). That is, for each dynamichardware system memory unit (i) in hop x, the (CF_MemUnit[x][i]) isexamined, and if (CF_MemUnit[x][i]<=CF_Threshold[x]), this memory unitis considered cache-friendly and can be moved. This is performed byidentifying free memory unit j in hop z or less important workloadmemory units j in hop z, as previous. Data is then copied from memoryunit i in hop x to newly freed memory unit j in hop z, and thecandidate's effective system is updated to show the new amount of memoryassigned to the system by updating the processor link to memory to pointto the new memory unit j in hop z. Finally, the memory unit i in hop xis freed to make it available for the target workloads of the targetsystem (represented as memory_needed=memory_needed−memoryunit(i)) (step1268).

Subsequent to moving the candidate memory and freeing the memory unitsto be allocated to the target system, the memory unit counter i isincremented (i=i+1), and if the candidate system's SLA production isclose to or missing its SLA requirement and the system is considered tobe cache-friendly, the processor clock speed is increased to reduce thealready low impact of the previous memory reallocation (step 1270). Themethod 1250 then determines whether the amount of memory needed has beenfreed by moving the cache-friendly memory units (step 1272), and if so,the method 1250 ends successfully (step 1262). If the amount of memoryrequested has not been freed at step 1272, a determination is then made(step 1276) as to whether additional memory units exist in the targetsystem's service class. If no additional memory units exist in thetarget system's service class, the method ends unsuccessfully (step1278). Otherwise, the next candidate memory unit in the target system'sservice class is examined (step 1274), and the method 1250 returns todetermining whether this memory unit exhibits cache-friendly behaviorand may be reallocated at step 1268.

The present invention may be an apparatus, a system, a method, and/or acomputer program product. The computer program product may include acomputer readable storage medium (or media) having computer readableprogram instructions thereon for causing a processor to carry outaspects of the present invention.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a local area network, awide area network and/or a wireless network. The network may comprisecopper transmission cables, optical transmission fibers, wirelesstransmission, routers, firewalls, switches, gateway computers and/oredge servers. A network adapter card or network interface in eachcomputing/processing device receives computer readable programinstructions from the network and forwards the computer readable programinstructions for storage in a computer readable storage medium withinthe respective computing/processing device.

Computer readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, or either source code or object code written in anycombination of one or more programming languages, including an objectoriented programming language such as Smalltalk, C++ or the like, andconventional procedural programming languages, such as the “C”programming language or similar programming languages. The computerreadable program instructions may execute entirely on the user'scomputer, partly on the user's computer, as a stand-alone softwarepackage, partly on the user's computer and partly on a remote computeror entirely on the remote computer or server. In the latter scenario,the remote computer may be connected to the user's computer through anytype of network, including a local area network (LAN) or a wide areanetwork (WAN), or the connection may be made to an external computer(for example, through the Internet using an Internet Service Provider).In some embodiments, electronic circuitry including, for example,programmable logic circuitry, field-programmable gate arrays (FPGA), orprogrammable logic arrays (PLA) may execute the computer readableprogram instructions by utilizing state information of the computerreadable program instructions to personalize the electronic circuitry,in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer readable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the Figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the block may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be executed substantially concurrently, or the blocks maysometimes be executed in the reverse order, depending upon thefunctionality involved. It will also be noted that each block of theblock diagrams and/or flowchart illustration, and combinations of blocksin the block diagrams and/or flowchart illustration, can be implementedby special purpose hardware-based systems that perform the specifiedfunctions or acts or carry out combinations of special purpose hardwareand computer instructions.

What is claimed is:
 1. A method for optimizing dynamic resourceallocations in a disaggregated computing environment, by a processordevice, comprising: tracking data access patterns of data elementsacross predetermined windows of time, the data elements used inexecution of a set of workloads, wherein the tracked data accesspatterns are assembled into a heat map, the heat map includinginformation on a workload data scope and a most recent access patternincluding a most recent access location of the data elements;categorizing the set of workloads into at least one of a plurality ofclasses, each class characterized by a method of data access of the dataelements during the tracking of the data access patterns, wherein thedata access patterns recorded in the heat map include an indication of apercentage and quantity of data requests of the data elements werefulfilled by each of a plurality of specific individual hardwareresources, and wherein the heat map includes additional information of acost per bit versus a locality of the data elements, as determined bythe most recent access location, relative to respective others of thespecific individual hardware resources that execute the set ofworkloads; and optimizing resource allocations in the disaggregatedcomputing environment for a current iteration of the set of workloadsbased on the information and the additional information in the heat mapby allocating at least a portion of the specific individual hardwareresources, each selected from respective pools of the hardware resourceswithin the disaggregated computing environment, to the current iterationof the set of workloads according to the data access patterns inreal-time; wherein the specific individual hardware resources eachcontribute only a portion of processing of the current iteration of theset of workloads notwithstanding each of the specific individualhardware resources are assigned to a single dynamically composedcomputing node executing the current iteration of the set of workloadsirrespective of a physical location of the pools to which the specificindividual hardware resources reside.
 2. The method of claim 1, whereinthe optimizing further comprises optimizing a balance between an overalldisaggregated framework utilization and a performance of eachdynamically constructed hardware system within the disaggregatedcomputing environment.
 3. The method of claim 2, further includingcategorizing a set of the dynamically constructed hardware systems intothe at least one of the plurality of classes by allocating the specificindividual hardware resources associated with respective ones of theclasses to each respective dynamically constructed hardware system. 4.The method of claim 1, wherein the plurality of classes include: acache-friendly class wherein the data elements exhibit data accesspatterns of having cache hits over a certain threshold; a cache-needyclass wherein the data elements exhibit data access patterns determinedto become cache-friendly when additional cache is allocated; amemory-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied with memory resources; and astorage-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied using pre-fetched data in anappropriate storage medium.
 5. The method of claim 1, further includingupdating the heat map according to a sampling algorithm of a sampling ofthe tracked data access patterns, the sampling algorithm set as aparameter configurable by a system administrator.
 6. The method of claim5, further including performing the optimization at predeterminedintervals assigned by the system administrator or in response todetecting one of a set of special system triggers.
 7. The method ofclaim 6, wherein the set of special system triggers are selected from agroup consisting of an initial allocation of a new dynamic hardwaresystem, a hardware component failure, a system alert of performancedegradation, and a Service Level Agreement (SLA) violation.
 8. A systemfor optimizing dynamic resource allocations in a disaggregated computingenvironment, the system comprising: a processor device executinginstructions stored in a memory device, wherein the processor device:tracks data access patterns of data elements across predeterminedwindows of time, the data elements used in execution of a set ofworkloads, wherein the tracked data access patterns are assembled into aheat map, the heat map including information on a workload data scopeand a most recent access pattern including a most recent access locationof the data elements; categorizes the set of workloads into at least oneof a plurality of classes, each class characterized by a method of dataaccess of the data elements during the tracking of the data accesspatterns, wherein the data access patterns recorded in the heat mapinclude an indication of a percentage and quantity of data requests ofthe data elements were fulfilled by each of a plurality of specificindividual hardware resources, and wherein the heat map includesadditional information of a cost per bit versus a locality of the dataelements, as determined by the most recent access location, relative torespective others of the specific individual hardware resources thatexecute the set of workloads; and optimizes resource allocations in thedisaggregated computing environment for a current iteration of the setof workloads based on the information and the additional information inthe heat map by allocating at least a portion of the specific individualhardware resources, each selected from respective pools of the hardwareresources within the disaggregated computing environment, to the currentiteration of the set of workloads according to the data access patternsin real-time; wherein the specific individual hardware resources eachcontribute only a portion of processing of the current iteration of theset of workloads notwithstanding each of the specific individualhardware resources are assigned to a single dynamically composedcomputing node executing the current iteration of the set of workloadsirrespective of a physical location of the pools to which the specificindividual hardware resources reside.
 9. The system of claim 8, whereinthe optimizing further comprises optimizing a balance between an overalldisaggregated framework utilization and a performance of eachdynamically constructed hardware system within the disaggregatedcomputing environment.
 10. The system of claim 9, wherein the processordevice categorizes a set of the dynamically constructed hardware systemsinto the at least one of the plurality of classes by allocating thespecific individual hardware resources associated with respective onesof the classes to each respective dynamically constructed hardwaresystem.
 11. The system of claim 8, wherein the plurality of classesinclude: a cache-friendly class wherein the data elements exhibit dataaccess patterns of having cache hits over a certain threshold; acache-needy class wherein the data elements exhibit data access patternsdetermined to become cache-friendly when additional cache is allocated;a memory-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied with memory resources; and astorage-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied using pre-fetched data in anappropriate storage medium.
 12. The system of claim 8, wherein theprocessor device updates the heat map according to a sampling algorithmof a sampling of the tracked data access patterns, the samplingalgorithm set as a parameter configurable by a system administrator. 13.The system of claim 12, wherein the processor device performs theoptimization at predetermined intervals assigned by the systemadministrator or in response to detecting one of a set of special systemtriggers.
 14. The system of claim 13, wherein the set of special systemtriggers are selected from a group consisting of an initial allocationof a new dynamic hardware system, a hardware component failure, a systemalert of performance degradation, and a Service Level Agreement (SLA)violation.
 15. A computer program product for optimizing dynamicresource allocations in a disaggregated computing environment, by aprocessor device, the computer program product embodied on anon-transitory computer-readable storage medium having computer-readableprogram code portions stored therein, the computer-readable program codeportions comprising: an executable portion that tracks data accesspatterns of data elements across predetermined windows of time, the dataelements used in execution of a set of workloads, wherein the trackeddata access patterns are assembled into a heat map, the heat mapincluding information on a workload data scope and a most recent accesspattern including a most recent access location of the data elements; anexecutable portion that categorizes the set of workloads into at leastone of a plurality of classes, each class characterized by a method ofdata access of the data elements during the tracking of the data accesspatterns, wherein the data access patterns recorded in the heat mapinclude an indication of a percentage and quantity of data requests ofthe data elements were fulfilled by each of a plurality of specificindividual hardware resources, and wherein the heat map includesadditional information of a cost per bit versus a locality of the dataelements, as determined by the most recent access location, relative torespective others of the specific individual hardware resources thatexecute the set of workloads; and an executable portion that optimizesresource allocations in the disaggregated computing environment for acurrent iteration of the set of workloads based on the information andthe additional information in the heat map by allocating at least aportion of the specific individual hardware resources, each selectedfrom respective pools of the hardware resources within the disaggregatedcomputing environment, to the current iteration of the set of workloadsaccording to the data access patterns in real-time; wherein the specificindividual hardware resources each contribute only a portion ofprocessing of the current iteration of the set of workloadsnotwithstanding each of the specific individual hardware resources areassigned to a single dynamically composed computing node executing thecurrent iteration of the set of workloads irrespective of a physicallocation of the pools to which the specific individual hardwareresources reside.
 16. The computer program product of claim 15, whereinthe optimizing further comprises optimizing a balance between an overalldisaggregated framework utilization and a performance of eachdynamically constructed hardware system within the disaggregatedcomputing environment.
 17. The computer program product of claim 16,further including an executable portion that categorizes a set of thedynamically constructed hardware systems into the at least one of theplurality of classes by allocating the specific individual hardwareresources associated with respective ones of the classes to eachrespective dynamically constructed hardware system.
 18. The computerprogram product of claim 15, wherein the plurality of classes include: acache-friendly class wherein the data elements exhibit data accesspatterns of having cache hits over a certain threshold; a cache-needyclass wherein the data elements exhibit data access patterns determinedto become cache-friendly when additional cache is allocated; amemory-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied with memory resources; and astorage-friendly class wherein the data elements exhibit data accesspatterns determined to be best satisfied using pre-fetched data in anappropriate storage medium.
 19. The computer program product of claim15, further including an executable portion that updates the heat mapaccording to a sampling algorithm of a sampling of the tracked dataaccess patterns, the sampling algorithm set as a parameter configurableby a system administrator.
 20. The computer program product of claim 19,further including an executable portion that performs the optimizationat predetermined intervals assigned by the system administrator or inresponse to detecting one of a set of special system triggers.
 21. Thecomputer program product of claim 20, wherein the set of special systemtriggers are selected from a group consisting of an initial allocationof a new dynamic hardware system, a hardware component failure, a systemalert of performance degradation, and a Service Level Agreement (SLA)violation.